fix: 修复配额说明重复和undefined问题

- 在editStorageForm中初始化oss_storage_quota_value和oss_quota_unit
- 删除重复的旧配额说明块，保留新的当前配额设置显示

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/node_modules/tar-stream/constants.js

@@ -0,0 +1,14 @@
+const constants = { // just for envs without fs
+  S_IFMT: 61440,
+  S_IFDIR: 16384,
+  S_IFCHR: 8192,
+  S_IFBLK: 24576,
+  S_IFIFO: 4096,
+  S_IFLNK: 40960
+}
+
+try {
+  module.exports = require('fs').constants || constants
+} catch {
+  module.exports = constants
+}